Fantasy Routing

Fantasy Routing

Fantasy Routing is a RouterOS feature designed to generate large numbers of dummy routing entries for testing purposes. It provides a fast and simple mechanism to populate the routing table with test routes, enabling administrators to evaluate routing performance, test convergence behavior, and validate configurations under load conditions.

The primary advantage of Fantasy Routing over script-based route generation is speed and simplicity. Routes can be generated rapidly from a single rule, and cleanup is straightforward — disabling the fantasy rule removes all generated routes immediately.

Fantasy Routing Fundamentals

Fantasy Routing uses a random number generator seeded from the route sequence number and configurable seed parameters to generate route prefixes. This approach ensures reproducible route sets for consistent testing across multiple runs, while also supporting varied distributions through seed adjustments.

Generated routes appear in the routing table as standard unicast routes and participate in normal route selection. This makes Fantasy Routing useful for simulating large-scale routing environments without requiring actual upstream connectivity.

Key characteristics:

• Easy cleanup: Disabling a fantasy rule immediately removes all routes it generated.
• Random generation: Routes are generated using a seeded random algorithm based on sequence numbers and configured parameters.
• Testing focus: Fantasy routes are intended for performance testing and validation, not production routing.

Configuration

Sub-menu

Sub-menu: /routing fantasy

Basic Configuration

Fantasy rules specify the number of routes to generate, the prefix range, and other generation parameters:

# View fantasy routing configuration
/routing fantasy print

# Add a fantasy rule to generate test routes
/routing fantasy rule add

# Disable a fantasy rule (removes all generated routes)
/routing fantasy rule disable 0

# Enable a fantasy rule (regenerates routes)
/routing fantasy rule enable 0

Monitoring Generated Routes

# View routes generated by fantasy routing
/ip route print where fantasy

# Count generated routes
/ip route print count-only where fantasy

Use Cases

Performance testing: Generate thousands of routes to evaluate routing table lookup performance and convergence timing under realistic load.

Configuration validation: Populate the routing table with test routes to verify that filters, policies, and routing rules behave correctly before production deployment.

Protocol testing: Test how routing protocols handle large routing tables by injecting test routes alongside real protocol-learned routes.

Related Documentation

• OSPF - Open Shortest Path First routing protocol
• BGP - Border Gateway Protocol for inter-domain routing
• Route - Routing table management
• Route Selection and Filters - Route filtering and policy configuration